Abstract: Session B  8:50 am (Back to Session B)
Using 3D Laser Scanning to Measure Bank Erosion – A Pilot Study                                         

Jillian Cole
Stantec Consulting
Towson, MD                                                                             

Authors:  Jillian L. Cole, Matthew LaJoie                                           

While working with the Ashokan Watershed Stream Management Program (AWSMP) to develop a bank erosion rating curve specific to the Ashokan Reservoir watershed located in Upstate New York, Stantec and AWSMP incorporated a pilot project to evaluate the use of 3D laser scanners to measure bank erosion. Traditionally, bank erosion is estimated by measuring the sediment loss at a single cross section location and applying that value to the length of the eroding bank. Laser scanners, however, can rapidly collect data along the entire bank surface. If a 3D scanner can collect an accurate surface of the eroding stream bank, a more precise measurement of total bank erosion/sediment loss could be obtained. The pilot study was designed to test the data quality, limitations, and cost-effectiveness of using 3D laser scanners. Three study sites were selected to have data collected with the 3D scanner in addition to the traditional cross section method. The study sites were chosen to represent common bank conditions found within the watershed including banks with thick vegetation, dense root masses, overhanging banks and large woody debris. The goal of the pilot study was to test the ability of the 3D scanner to accurately depict the surface of the bank through these types of obstructions. This presentation will discuss the results of data collection, a comparison of traditional methods to 3D scanning, and the accuracy, applicability and limitations of each method.